Method for optimizing 2-alkyl anthracene oxidation process based on feeding mode

Abstract

The invention relates to the field of preparation of 2-alkyl anthracene, and discloses a method for optimizing a 2-alkyl anthracene oxidation process based on a feeding mode, which comprises the following steps: adding a solution containing 2-alkyl anthracene and a catalyst into an oxidation reactor through feeding, and reacting in an oxygen-deficient environment to obtain a mixture containing 2-alkyl anthraquinone, and the feeding mode is continuous feeding. The concentration of 2-alkyl anthracene in the oxidation reactor can be controlled through the feeding rate by selecting a continuous feeding mode; the concentration of the 2-alkylanthracene in the oxidation reactor of the continuous feeding process is low, so that the conversion rate of the 2-alkylanthracene and the selectivity of the 2-alkylanthraquinone are remarkably improved, the content of tail oxygen is controlled within a safe range, and the economic benefit and the safety performance are increased.

Description

Technical Field

[0001] The invention relates to the field of preparation of 2-alkylanthracene, and in particular to a method for optimizing the oxidation process of 2-alkylanthracene based on a feeding mode. Background Art

[0002] 2-Alkylanthraquinone is a very important chemical raw material, which is widely used in the fields of medicine, dyes and hydrogen peroxide working fluid. When used as hydrogen peroxide working fluid, 2-alkylanthraquinone has higher solubility and hydrogen efficiency than 2-ethylanthraquinone. Therefore, researchers in the 2-alkylanthraquinone industry have been committed to developing a green and industrially promising process. At present, the main methods for the synthesis of 2-alkylanthraquinone are: (1) phthalic anhydride method; (2) alkylanthracene oxidation method; (3) naphthoquinone method.

[0003] (1) Phthalic anhydride method: The synthesis of 2-alkylanthraquinone by the phthalic anhydride method is mainly divided into two steps: first, phthalic anhydride and 2-alkylbenzene undergo Friedel-Crafts alkylation reaction under the catalysis of aluminum chloride to produce 2-(4-alkylbenzoyl)benzoic acid. The latter undergoes a ring-closure reaction under the catalysis of concentrated sulfuric acid to synthesize 2-alkylanthraquinone. This synthesis process has the advantages of easy availability of raw materials, simple process, high yield and low cost. Due to the use of aluminum chloride and concentrated sulfuric acid, it is highly corrosive to equipment and will produce a large amount of waste liquid, so there is also an environmental problem. At present, the improvement direction of this process is mainly to develop green, efficient and environmentally friendly catalysts. For example, ionic liquids, solid acid catalysts, etc., but whether it can be applied industrially in advance needs further research.

[0004] (2) Alkyl anthracene oxidation method: The alkyl anthracene oxidation method for synthesizing 2-alkyl anthraquinone mainly includes two steps: first, anthracene undergoes Friedel-Crafts alkylation reaction with alcohol to generate 2-alkyl anthracene, which then undergoes oxidation reaction with air or oxygen to generate 2-alkyl anthraquinone. This process is simple and environmentally friendly, but the main problems currently exist are that the raw material anthracene is not easy to obtain and the alkylation conversion rate and selectivity are low.

[0005] (3) Naphthoquinone method: The steps for synthesizing 2-alkylanthraquinone by the naphthoquinone method are relatively complicated, including the following steps: first, 2-pentyl-1,3-butadiene and 1,4-naphthoquinone are used as raw materials to undergo a Diels-Alder cycloaddition reaction to generate 2-pentyl-1,4-dihydroanthracene, and then an oxidation reaction with air or oxygen is performed to generate 2-alkylanthraquinone. This process is green and environmentally friendly, but the synthesis of raw materials is relatively difficult and is not suitable for industrialization.

[0006] Among them, the phthalic anhydride method has environmental problems, and the raw materials of the naphthoquinone method are not easy to synthesize. The alkyl anthracene oxidation method is green and environmentally friendly and has a simple process, which is a process more suitable for industrialization. Because 2-alkyl anthracene has a high melting point, the industry recommends the use of a stirred tank reactor. In the method of separating 2-alkyl anthracene from a product containing alkyl anthracene and preparing 2-alkyl anthraquinone using a catalytic oxidation process, the alkyl anthracene oxidation method is adopted in China Patent Publication No. CN111825545A, 2-alkyl anthracene is contacted with an oxidant by using an oxidant hydrogen peroxide for oxidation reaction, and 2-alkyl anthracene is separated from the product and oxidized to obtain 2-alkyl anthraquinone. However, the conversion rate of the oxidation reaction is not high enough, and the prior art has less research on the feeding conditions. For systems with side reactions, optimizing the feeding conditions will also significantly affect the performance of the reactor. Summary of the invention

[0007] The present invention aims to overcome the problem that the conversion rate of 2-alkyl anthraquinone in the prior art alkyl anthracene oxidation method is low and the process needs to be optimized, and provides a method for optimizing the 2-alkyl anthracene oxidation process based on a feeding mode. The present invention proposes a continuous feeding mode, adjusts the state of 2-alkyl anthracene and a catalyst when continuously fed, and by using the process, the purpose of high conversion rate and high yield can be achieved.

[0008] In order to achieve the above object, the present invention adopts the following technical solutions: The present invention proposes a method for optimizing a 2-alkyl anthracene oxidation process based on a feeding method, comprising the following steps: adding a reaction solution into an oxidation reactor through a feeding method to react in an oxygen-deficient environment to obtain a mixture containing 2-alkyl anthraquinone, wherein the feeding method is continuous feeding. The continuous feeding method can control the concentration of 2-alkyl anthracene in the oxidation reactor by the feeding rate. Compared with the one-time feeding in the prior art, the concentration of 2-alkyl anthracene in the oxidation reactor of the continuous feeding process is lower, and the yield of 2-alkyl anthraquinone can be effectively improved.

[0009] Preferably, the reaction solution is a mixture of a 2-alkyl anthracene solution and a catalyst. The concentration of the 2-alkyl anthracene solution is 0.1-0.4 g / L. The use of a liquid reaction solution can make the 2-alkyl anthracene in the oxidation reactor react more completely and fully contact, thereby increasing the yield of 2-alkyl anthraquinone.

[0010] Preferably, the mass ratio of the 2-alkylanthracene solution to the catalyst in the reaction solution is 0.5-2:20-40.

[0011] Preferably, the feeding rate of continuous feeding is 500-1000kg / h. By adjusting the feeding rate, operators can quickly respond to and optimize the production process according to actual production needs and market changes, and achieve stable product quality and flexible adjustment of output.

[0012] Preferably, the catalyst is one of sulfuric acid, nitric acid, hydrochloric acid, hydrofluoric acid and hydrobromic acid.

[0013] Preferably, the reaction temperature is 60-180°C.

[0014] Preferably, the reaction pressure is 0.5-4 MPa.

[0015] Preferably, the oxygen content of the oxygen-deficient environment is less than 8% by volume.

[0016] Preferably, the reaction solution is introduced from the top of the oxidation reactor for reaction.

[0017] Preferably, the oxygen-deficient environment is adjusted by introducing air into the bottom of the oxidation reactor to adjust the oxygen content.

[0018] Therefore, the present invention has the following beneficial effects: (1) by optimizing the 2-alkylanthracene oxidation process by using a continuous feeding method, a higher yield of 2-alkylanthraquinone can be obtained; (2) by optimizing the 2-alkylanthracene oxidation process by using a continuous feeding method, the stability and flexibility of the production process are enhanced. BRIEF DESCRIPTION OF THE DRAWINGS

[0019] Figure 1 It is a diagram of the reaction apparatus of Example 1 of the present invention.

[0020] Figure 2 It is a diagram of the reaction device of Comparative Example 1 of the present invention.

[0021] Figure 3 It is a diagram of the reaction device of Comparative Example 2 of the present invention.

[0022] In the figure: motor-1, gas distributor-2, oxidation reactor-3, reaction solution feed port-4, catalyst feed port-5, 2-alkyl anthracene feed port-6.

[0023] Figure 4 It is a graph showing the change in 2-alkylanthracene concentration in Example 1 of the present invention and Comparative Example 2. DETAILED DESCRIPTION

[0024] The present invention is further described in detail below in conjunction with the examples and drawings, but the embodiments of the present invention are not limited thereto. If specific conditions are not specified in the examples, they are carried out according to conventional conditions or conditions recommended by the manufacturer. If the manufacturer of the reagents or instruments used is not specified, they are all conventional products that can be purchased commercially.

[0025] The present invention proposes a method for optimizing the 2-alkyl anthracene oxidation process based on a feeding method, comprising the following steps: S1, adding a reaction solution into an oxidation reactor through feeding to react in an oxygen-deficient environment to obtain a mixture containing 2-alkyl anthracenequinone, and the feeding method is continuous feeding. The continuous feeding method can control the concentration of 2-alkyl anthracene in the oxidation reactor by the feeding rate. Compared with the one-time feeding of the prior art, the concentration of 2-alkyl anthracene in the oxidation reactor of the continuous feeding process is lower, which can effectively improve the yield of 2-alkyl anthracenequinone. In the chemical production process, the continuous feeding method is used to feed the reactor, which is a highly optimized and significantly efficient operation strategy. The core advantage of this method is that it can achieve dynamic equilibrium control of the concentration of 2-alkyl anthracene, a key reactant inside the oxidation reactor, by accurately controlling the feeding rate. Compared with the traditional one-time feeding method, continuous feeding not only avoids the unfavorable conditions such as excessive local concentration and sudden changes in temperature and pressure caused by the sudden influx of materials, but also makes the reaction process more stable and controllable. Specifically, when continuous feeding is used, 2-alkyl anthracene continuously enters the oxidation reactor at a stable rate, and its concentration is maintained at a relatively low and stable level during this process. This low and stable concentration environment creates more gentle and uniform conditions for subsequent chemical reactions, reducing the problem of side reactions or decreased product selectivity caused by concentration fluctuations. More importantly, for the reaction of generating the target product 2-alkyl anthraquinone, a lower 2-alkyl anthraquinone concentration can often promote the smooth progress of the main reaction path, inhibit the generation of unnecessary by-products, and thus effectively improve the yield of the target product 2-alkyl anthraquinone. In addition, the continuous feeding process also brings about a significant improvement in operational flexibility. By adjusting the feed rate, operators can quickly respond and optimize the production process according to actual production needs and market changes, and achieve stable product quality and flexible adjustment of output. This flexibility is of great significance for improving production efficiency, reducing production costs and enhancing market competitiveness. In summary, the use of continuous feeding to control the concentration of 2-alkyl anthraquinone in the oxidation reactor not only optimizes the reaction conditions, improves the yield of 2-alkyl anthraquinone, but also enhances the stability and flexibility of the production process.

[0026] In some embodiments provided by the present invention, the reaction solution is a mixture of a 2-alkyl anthracene solution and a catalyst, and the concentration of the 2-alkyl anthracene solution is 0.1-0.4 g / L. The use of a liquid reaction solution can make the 2-alkyl anthracene in the oxidation reactor react more completely and fully contact, thereby increasing the yield of 2-alkyl anthraquinone.

[0027] In some embodiments provided by the present invention, the mass ratio of the 2-alkylanthracene solution to the catalyst in the reaction solution is 0.5-2:20-40.

[0028] In some embodiments provided by the present invention, the feed rate of the continuous feed is 500-1000 kg / h.

[0029] In some embodiments provided herein, the catalyst is one of sulfuric acid, nitric acid, hydrochloric acid, hydrofluoric acid, and hydrobromic acid.

[0030] In some embodiments provided by the present invention, the reaction temperature is 60-180°C.

[0031] In some embodiments provided by the present invention, the reaction pressure is 0.5-4 MPa. According to the specific reaction system, the optimal reaction temperature and pressure are adjusted to help accelerate the reaction rate and improve the yield of the product.

[0032] In some embodiments provided herein, the oxygen content of the oxygen-depleted environment is less than 8% by volume.

[0033] In some embodiments provided by the present invention, the reaction solution is introduced from the top of the oxidation reactor for reaction.

[0034] In some embodiments provided by the present invention, the oxygen-deficient environment adjusts the oxygen content by introducing air into the bottom of the oxidation reactor. In order to continuously provide the oxygen required for oxidation in the reaction system, the air is carefully regulated and introduced from the bottom of the oxidation reactor through a gas distributor. The design of the gas distributor ensures that the air can be evenly dispersed throughout the reaction solution, thereby increasing the contact area between oxygen and reactants and the reaction efficiency. In addition, the amount of air introduced is not fixed, but is dynamically regulated according to the concentration of oxygen in the tail gas. Specifically, by real-time monitoring of the oxygen content in the tail gas (maintained below 8%), and adjusting the air flow rate accordingly, it is ensured that the oxygen concentration in the reaction system is always maintained within the optimal range, so as not to waste resources excessively, nor to limit the reaction rate and product yield due to insufficient oxygen.

[0035] Overall embodiment The present invention proposes a method for optimizing the 2-alkylanthracene oxidation process based on the feed mode. Figure 1The process shown in the figure is to carry out oxidation of 2-alkylanthracene. The reaction solution is continuously fed into the oxidation reactor 3 from the top of the oxidation reactor 3 through the reaction solution feeding port 4. The motor 1 is started to stir synchronously. Oxygen is introduced into the bottom of the oxidation reactor 3 through the gas distributor 2 to make the reaction environment an oxygen-deficient environment. The catalyst is selected from sulfuric acid, nitric acid, hydrochloric acid, hydrofluoric acid and hydrobromic acid. Under the reaction conditions of temperature of 60-180°C and pressure of 0.5-4MPa, a certain amount of 2-alkylanthracene solution with a concentration of 0.1-0.4g / L and catalyst solution are combined to form a reaction solution. The reaction solution is continuously fed from the top of the oxidation reactor at a feeding rate of 500-1000kg / h. Then, air is continuously introduced from the gas distributor, and the gas flow rate is controlled according to tail oxygen (less than 8%). The feeding time of the solution continuous feeding is 8h, and the reaction time is 9h.

[0036] Example 1 The present invention proposes a method for optimizing the 2-alkylanthracene oxidation process based on the feed mode. Figure 1 The process flow shown is for 2-alkylanthracene oxidation. Sulfuric acid is selected as the catalyst. Under the reaction conditions of temperature of 160°C and pressure of 3MPa, a certain amount of 0.3g / L 2-alkylanthracene solution and sulfuric acid catalyst are continuously added to the oxidation reactor from the top of the oxidation reactor at a feeding rate of 500kg / h, and then oxygen is introduced from the bottom through the gas distributor 2, and the gas amount is regulated according to the tail oxygen (less than 8%). The feeding time of the solution continuous feeding is 8h, and the reaction time is 9h.

[0037] Example 2 The present invention proposes a method for optimizing the 2-alkylanthracene oxidation process based on the feed mode. Figure 1 The process flow shown is used for 2-alkylanthracene oxidation. Nitric acid is selected as the catalyst. Under the reaction conditions of temperature of 60°C and pressure of 0.5MPa, a 2-alkylanthracene solution with a concentration of 0.4g / L and a nitric acid catalyst equivalent to that of Example 1 are continuously added to the oxidation reactor from the top of the oxidation reactor at a feeding rate of 500kg / h, and then oxygen is introduced from the bottom through a gas distributor, and the gas amount is regulated according to the tail oxygen (less than 8%). The feeding time of the solution continuous feeding is 8h, and the reaction time is 9h.

[0038] Example 3 The present invention proposes a method for optimizing the 2-alkylanthracene oxidation process based on the feed mode. Figure 1The process flow shown is used for 2-alkylanthracene oxidation. Sulfuric acid is used as the catalyst. Under the reaction conditions of temperature of 160°C and pressure of 3MPa, a 0.2g / L 2-alkylanthracene solution and a hydrofluoric acid catalyst equivalent to those in Example 1 are continuously added to the oxidation reactor from the top of the oxidation reactor at a feeding rate of 1000kg / h, and then oxygen is introduced from the bottom through a gas distributor, and the gas amount is regulated according to the tail oxygen (less than 8%). The feeding time of the solution continuous feeding is 8h, and the reaction time is 9h.

[0039] Example 4 The present invention proposes a method for optimizing the 2-alkylanthracene oxidation process based on the feed mode. Figure 1 The process flow shown is used for 2-alkylanthracene oxidation. Hydrobromic acid is selected as the catalyst. Under the reaction conditions of temperature of 180°C and pressure of 4MPa, a 0.1g / L 2-alkylanthracene solution and a hydrobromic acid catalyst equivalent to those in Example 1 are continuously added to the oxidation reactor from the top of the oxidation reactor at a feeding rate of 1000kg / h, and then oxygen is introduced from the bottom through a gas distributor, and the gas amount is regulated according to the tail oxygen (less than 8%). The feeding time of the solution continuous feeding is 8h, and the reaction time is 9h.

[0040] Comparative Example 1 (2-Alkylanthracene Single Feed) The present invention proposes a method for optimizing the 2-alkylanthracene oxidation process based on the feed mode. Figure 2 The process flow shown is used to oxidize 2-alkyl anthracene. The 2-alkyl anthracene solution of the same amount as that of Example 1 is added from the top of the oxidation reactor 3 at one time, and then oxygen is introduced from the bottom through the gas distributor 2. The motor 1 is stirred synchronously, and the gas amount is regulated according to the tail oxygen (less than 8%). The solution reaction time is 9 hours.

[0041] Comparative Example 2 (2-Alkylanthracene Solid and Catalyst Continuously Fed) The present invention proposes a method for optimizing the 2-alkylanthracene oxidation process based on the feed mode. Figure 3 The process shown is for 2-alkylanthracene oxidation, the catalyst is continuously fed through the catalyst feed port 5, and the 2-alkylanthracene solid is continuously fed through the 2-alkylanthracene feed port 6. Sulfuric acid is selected as the catalyst. First, the solvent equal to that in Example 1 is put into the oxidation reactor 3, and then the 2-alkylanthracene solid and the sulfuric acid catalyst are continuously added to the reactor, and the feeding rate is 100kg / h. At the same time, oxygen is continuously introduced into the oxidation reactor through the gas distributor 2, and the motor 1 is stirred synchronously, and the gas amount is regulated according to the tail oxygen (less than 8%). The feeding time of continuous feeding is 8h, and the reaction time is 9h.

[0042] Comparative Example 3 The present invention proposes a method for optimizing the 2-alkylanthracene oxidation process based on the feed mode. Figure 1 The process flow shown in the figure is for 2-alkylanthracene oxidation process. Sulfuric acid is used as the catalyst. Under the reaction conditions of temperature of 50°C and pressure of 5MPa, a 2-alkylanthracene solution with a concentration of 0.3g / L equivalent to that of Example 1 is continuously added to the oxidation reactor from the top of the oxidation reactor at a feeding rate of 400kg / h, and then oxygen is introduced from the bottom through a gas distributor, and the gas amount is regulated according to the tail oxygen (less than 8%). The feeding time of the solution continuous feeding is 8h, and the reaction time is 9h.

[0043] Comparative Example 4 The present invention proposes a method for optimizing the 2-alkylanthracene oxidation process based on the feed mode. Figure 1 The process flow shown is used for 2-alkyl anthracene oxidation. Sulfuric acid is selected as the catalyst. Under the reaction conditions of temperature of 200°C and pressure of 5MPa, a 0.3g / L 2-alkyl anthracene solution equivalent to that in Example 1 is continuously added to the oxidation reactor from the top of the oxidation reactor at a feeding rate of 1200kg / h, and then oxygen is introduced from the bottom through a gas distributor, and the gas amount is regulated according to the tail oxygen (less than 8%). The feeding time of the solution continuous feeding is 8h, and the reaction time is 9h.

[0044] In the present invention, the calculation formula for the yield of 2-alkylanthraquinone (2-AAQ) is as follows: Among them, Y 2-AAQ is the yield of 2-alkylanthraquinone, m 2-AAN is the feed mass flow rate of 2-alkylanthracene, M 2-C5AN is the relative molecular mass of 2-alkylanthracene, c 2-AAN,in ,c 2-AAQ,in is the feed concentration of 2-alkylanthracene and 2-alkylanthraquinone, c 2-C5AN ,c 2-C5AQ is the concentration of 2-alkylanthracene and 2-alkylanthraquinone in the oxidation reactor, v is the feed volume flow rate, t feed is the feeding time, V R is the effective volume of the oxidation reactor.

[0045] By adopting the above-mentioned embodiment and comparative example, the yield calculation formula of 2-alkylanthraquinone (2-AAQ) was used to obtain the yield results as shown in the following table. Serial number 2-Alkylanthraquinone yield / % Example 1 97.8 Example 2 52.3 Example 3 87.3 Example 4 85.8 Comparative Example 1 84.2 Comparative Example 2 89.5 Comparative Example 3 2.4 Comparative Example 4 72.1

[0046] By comparing Example 1 with Comparative Example 1, the feeding methods are different. Example 1 uses a method of continuously feeding 2-alkyl anthracene solution and catalyst solution into an oxidation reactor to perform an oxidation reaction to generate 2-alkyl anthraquinone. Figure 1 As shown in Comparative Example 1, a 2-alkyl anthracene solution and a catalyst are added into an oxidation reactor in a one-time feeding manner to perform an oxidation reaction to generate 2-alkyl anthraquinone. Figure 2 As shown. By comparing the yields of 2-alkylanthraquinone, the yield of 2-alkylanthraquinone in Example 1 is 97.8%, and the yield of 2-alkylanthraquinone in Comparative Example 1 is 84.2%. According to the comparison of the yields of 2-alkylanthraquinone, it can be clearly seen that the continuous feeding method selected in Example 1 has a more obvious improvement in the yield of 2-alkylanthraquinone than the one-time feeding method in Comparative Example 1. On this basis, the present invention proposes another comparative example, in which 2-alkylanthracene and the catalyst are fed separately as Comparative Example 2. By comparing Example 1 with Comparative Example 2, different feeding methods are used. Comparative Example 2 uses a continuous feeding method, but the solvent is put into the oxidation reactor in advance, and then the 2-alkylanthracene and the catalyst are continuously fed, such as Figure 3 As shown. By comparing the yields of 2-alkylanthraquinone, the yield of 2-alkylanthraquinone in Example 1 is 97.8%, and the yield of 2-alkylanthraquinone in Comparative Example 2 is 89.5%. According to the comparison of the yields of 2-alkylanthraquinone, it can be clearly seen that the continuous feeding method selected in Example 1 has a more obvious improvement in the yield of 2-alkylanthraquinone than the one-time feeding method in Comparative Example 2. At the same time, the yield of 2-alkylanthraquinone in Comparative Example 2 is also significantly higher than that in Comparative Example 1, but not as obvious as that in Example 1. This shows that the scheme proposed in Example 1 is significantly improved on the basis of the prior art. In addition, when the scheme of Comparative Example 2 uses 2-alkylanthracene and catalyst to be continuously fed, the concentration of 2-alkylanthracene is higher than the concentration of 2-alkylanthracene when the solution is continuously fed in Example 1 most of the time. Figure 4As shown. The concentration of 2-alkyl anthracene in the oxidation reactor of the continuous feeding process is low, which can effectively improve the yield of 2-alkyl anthraquinone. The same amount of 2-alkyl anthracene solution in Example 1 is continuously and evenly added to the oxidation reactor, and the feeding rate is accurately set to 500kg / h. The setting of this rate is based on a comprehensive consideration of the volume of the oxidation reactor, the stirring efficiency and the reaction kinetics, and is intended to ensure that the reactants can be fully mixed and reacted evenly in the oxidation reactor, and to avoid uneven reactions or product quality degradation caused by excessive or low local concentrations. Under the premise that the total volume and composition of the material remain unchanged, the 2-alkyl anthracene oxidation process of 2-alkyl anthracene fed once is changed to a process of continuous feeding of 2-alkyl anthracene and catalyst, and continuous feeding of 2-alkyl anthracene solution. The continuous feeding method is adopted to reduce the concentration of 2-alkyl anthracene in the oxidation reactor, which is conducive to improving the selectivity of 2-alkyl anthraquinone. This low and stable concentration environment creates more gentle and uniform conditions for subsequent chemical reactions, and reduces the problem of side reactions or decreased product selectivity caused by concentration fluctuations. More importantly, for the reaction of generating the target product 2-alkylanthraquinone, a lower 2-alkylanthracene concentration can often promote the smooth progress of the main reaction path, inhibit the generation of unnecessary by-products, and thus effectively improve the yield of the target product 2-alkylanthraquinone. In addition, when 2-alkylanthracene and catalyst are continuously fed, the concentration of 2-alkylanthracene is higher than the concentration of 2-alkylanthracene when the solution is continuously fed most of the time. This continuous feeding method helps to maintain the concentration of the reactants in the oxidation reactor stable, thereby ensuring the smooth progress of the reaction process and the uniformity of the product quality. Therefore, the feeding method of the present invention using the 2-alkylanthracene solution continuous feeding in Example 1 can effectively improve the conversion rate of 2-alkylanthraquinone.

[0047] By comparing the yields of 2-alkylanthraquinone in Example 1, Comparative Examples 3 and Comparative Examples 4, the yield of 2-alkylanthraquinone in Comparative Example 3 is only 2.4%, while the yield of 2-alkylanthraquinone in Comparative Example 4 is 72.1%. The scheme of Comparative Example 3 is set up with a temperature lower than the set temperature range of the present invention, and a low feed rate, which achieves a lower reaction concentration, but the yield of 2-alkylanthraquinone is abnormally low. It can be concluded that temperature is also an important choice in the scheme design of the present invention, and the temperature has a huge impact on the yield of 2-alkylanthraquinone. Comparative Example 4 is a higher reaction temperature, higher than the set temperature range of the present invention, a higher feed rate, and a lower yield of 2-alkylanthraquinone. It can be concluded that temperature is the main influencing factor, and the optimal temperature selected in Example 1 is a choice that has substantial progress in the process of the present invention.

[0048] The raw materials and equipment used in the present invention, unless otherwise specified, are all commonly used raw materials and equipment in the art; the methods used in the present invention, unless otherwise specified, are all conventional methods in the art.

[0049] The above description is only a preferred embodiment of the present invention and does not limit the present invention in any way. Any simple modification, change and equivalent transformation made to the above embodiment based on the technical essence of the present invention still falls within the protection scope of the technical solution of the present invention.

Claims

1. A method for optimizing a 2-alkylanthracene oxidation process based on a feed mode, characterized in that: The steps include: The reaction solution is added into an oxidation reactor through a feed to react in an oxygen-deficient environment to obtain a mixture containing 2-alkylanthraquinone; The feeding method is continuous feeding.

2. The method for optimizing the 2-alkylanthracene oxidation process based on the feed mode according to claim 1, characterized in that: The reaction solution is a mixture of a 2-alkylanthracene solution and a catalyst; The concentration of the 2-alkylanthracene solution is 0.1-0.4 g / L.

3. The method for optimizing the 2-alkylanthracene oxidation process based on the feed mode according to claim 2, characterized in that: The mass ratio of the 2-alkylanthracene solution to the catalyst in the reaction solution is 0.5-2:20-40.

4. A method for optimizing a 2-alkylanthracene oxidation process based on a feed mode according to claim 2 or 3, characterized in that: The feed rate for continuous feeding is 500-1000 kg / h.

5. The method for optimizing the 2-alkylanthracene oxidation process based on the feed mode according to claim 2, characterized in that: The catalyst is one of sulfuric acid, nitric acid, hydrochloric acid, hydrofluoric acid and hydrobromic acid.

6. The method for optimizing the 2-alkylanthracene oxidation process based on the feed mode according to claim 1, characterized in that: The reaction temperature is 60-180°C.

7. The method for optimizing the 2-alkylanthracene oxidation process based on the feed mode according to claim 1, characterized in that: The reaction pressure is 0.5~4MPa.

8. The method for optimizing the 2-alkylanthracene oxidation process based on the feed mode according to claim 1, characterized in that: An oxygen-depleted environment has an oxygen content of less than 8% by volume.

9. The method for optimizing the 2-alkylanthracene oxidation process based on the feed mode according to claim 1, characterized in that: The reaction solution is fed into the top of the oxidation reactor for reaction.

10. The method for optimizing the 2-alkylanthracene oxidation process based on the feed mode according to claim 1, characterized in that: The oxygen-deficient environment is adjusted by introducing air into the bottom of the oxidation reactor.

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